Furnace-stack



(No Model.) 7

J. HEATLEY.'

FURNACE STAOK.

Patented Nov. 20, 1888.

N. PETERS. Pnumum m hnr. Wahingwn. ac,

UNITED STATES PATENT JOHN HEATLEY, OF PlTTSBURG, PENNSYLVANIA.

FU RNACE-STAC K.

SPECIFICATION forming part of Letters Patent No. 393,332, dated November 20, 1888.

(No model.)

To all whom it may concern:

Be it known that I, JOHN HEA'ILEY, a citizen of the United States, residing at Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented an Improvement in Furnace-Stacks; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it pertainsto make and use the same, reference being had to the accompanying drawings, which form a part of this specification.

My invention relates to a device for protecting furnace -stacks and increasing their draft; and it consists of a shield or casing secured around the lower portion of stack in such a manner as to admit of a current of cold air entering the stack, together with certain details of construction and combination of parts, as will be fully described hereinafter.

In the accompanying drawings, Figure 1 is a vertical sectional elevation of an ordinary draft-stack, such as are in common use on all smelting-furnaces, and-provided with my improved protector constructed in accordance with my invention. Fig. 2 is a sectional plan view of the draftstack on theline mm. Fig. 3 is a sectional plan view taken on the line 1 y.

I put my invention into practice with a furnace-stack, a, such as is used in connection with a smelting-furnace, 1), consisting of a permanent stack, a, mounted on a plate, 0, supported by four posts, (1. This stack a may, if desired, be lined with refractory material 6. Projecting upward into the stack a is a short flue,f, communicating with the furnace, leaving an intervening space, 9, between the inner wall, e, of the stack a and the outer casing, h, of the fluef. Surrounding this short fluef, and secured to the plate a, is a shield or casing, '5, which leaves an air-space, 10, through which cold air may pass from a point near the base of the fluef upward into the draft-stack a. At the top of the fiuef are secured several brackets or braces, Z, which serve to support the same,the ends of which rest on the plate 0.

By reference to Fig. 1 on the drawings it will be seen that cold air entering the intervening space is between the shield i and the outer casing, h, of the flue f will travel upward into the furnacestack a, thereby cooling the fluef and the stack a. The shield or cover i may be of any desired size or length and extend back over a portion of the furnace at.

This device not only serves to prevent the fluef and stack a from burning out, but also increases the draft in the latter by means of the fresh supply of air entering the stack c.

Having thus described my invention, what I claim, and desire to secure by Letters Patent, 1s

The combinatiomwith a furnace and astack elevated above the furnace on a plate and uprights, of avertical pipe communicating with said furnace and entering the lower open end of said stack, the diameter of the pipe being less than the interior diameter of the stack, whereby a continuous space is provided be tween said flue and the interior walls of the stack, and a casing surrounding the pipe to leave a continuous annular space, the upper end of said interior casing being secured to said plate, and the lower end thereof being open for the admission of cold air between the central pipe, its casing, and the stack, substantially as and for the purpose described.

JOHN HEATLEY.

Witnesses:

O. 0. LEE, M. E. HARRISON. 

